A landslide granular phase transition

Abstract

Landslides appear in many different forms and sizes, from devastating debris flows to overly optimistic sand castles. A familiar and well-documented feature of all landslides is the positive correlation between volume and landslide runout. Larger landslides have a greater potential to reach farther. Here we explore the low volume limit and find a surprising negative correlation between volume and landslide runout. A decrease in volume leads to an increase in runout. In a series of experiments we systematically vary the landslide volume to reveal a transition between these two regimes.